Length adjuster mechanisms are commonly integrated into control cables used for push-pull applications. Such cables have a rod serving as the core at each end extending from the conduit. Adjuster mechanisms are widely used in control cables within automobiles, such as with transmission shift controls. Adjuster mechanisms serve as means of compensating for variation in distances between both mounting points of a cable core and mounting points of the corresponding cable conduit.
An option to providing an adjuster mechanism in the cable system is to provide a slot at either end of the cable system. The disadvantage of using a slot is in the amount of time required to assemble parts having slots. Typically a threaded fastener is used to achieve a clamping load necessary to prevent relative motion along the slot. Tightening a threaded fastener takes more time than does pushing in a snap-in type clip as is commonly used with cable systems having adjuster mechanisms.
Adjuster mechanisms are generally one of two types: a core length adjuster mechanism or a conduit length adjuster mechanism. Both change the effective length of the cable core.
Conduit adjuster mechanisms are commonly used, but tend to be large, making it difficult to package and install them in applications with limited space, such as in an engine compartment of a vehicle.
Conduit length adjuster mechanisms also present a potential for misadjustment whenever the cable routing is such that displacement of the conduit during adjustment is restricted. When the conduit cannot move freely, accurate adjustment is inhibited.
Known core length adjuster mechanisms are typically located at one of the ends of the cable core. More specifically, the adjuster mechanisms are at the end of the rod, or the rod end. The core length adjuster mechanisms generally integrate a swivelable attachment means, such as a socket for a ball and socket type arrangement, into the adjusting mechanism because the adjuster mechanisms are at one of the ends of the cable cores. Core length adjuster mechanisms are generally smaller than conduit type adjuster mechanisms, facilitating assembly operations where they are employed. Known core length adjuster mechanisms typically have a telescoping member molded to a rod end. The telescoping member is slidably disposed within a body into which the socket is integrated. A clip which is axially fixed relative to the body is used to lock the telescoping member to the body by pressing the clip into the body. A disadvantage of this arrangement is that it tends to result in a fairly long adjuster mechanism because the portion of the telescoping member with which the clip engages is disposed beyond the rod end. The engaging portion of the telescoping member extends forward in front of the rod end. Longer adjuster mechanisms increase the minimum required distance between the point where the conduit is fixed in place and a point of swivelable attachment for the rod end, thereby increasing packaging difficulties.
Another disadvantage of known core length adjuster mechanisms is that the telescoping member is permanently fixed to the rod end, usually by molding it to the rod end. This need to have the telescoping member fixed to the rod end increases the cost and complexity of manufacturing the cable system over what the cost would be if the telescoping member was not needed.